The growth and orientation of zeolite crystals on a glass substrate was investigated by changing the roughness and setting of the substrate surface.The orientation control of crystals on the glass substrate was achiev...The growth and orientation of zeolite crystals on a glass substrate was investigated by changing the roughness and setting of the substrate surface.The orientation control of crystals on the glass substrate was achieved.It was found that the setting and treatment of the glass substrate had a substantial effect on crystal orientation.When the substrate surface was upward, the preferential growth of crystal was along the a-axis.However, the preferential growth of crystal was along b-axis when the substrate surface was downward.According to experimental results, a film formation mechanism was proposed to account for the growth and orientation of crystals on the glass substrate.展开更多
Synthesis of high performance Silicalite-1 zeolite membranes on silica tubes was first reported in this paper.After two-step in-situ hydrothermal synthesis,well intergrown Silicalite-1 zeolite membranes were synthesiz...Synthesis of high performance Silicalite-1 zeolite membranes on silica tubes was first reported in this paper.After two-step in-situ hydrothermal synthesis,well intergrown Silicalite-1 zeolite membranes were synthesized on silica tubes after aging at 75 ℃ for 12 h.The Silicalite-1 zeolite membranes were characterized by SEM.The separation performance towards ethanol/water mixtures was evaluated by pervaporation.With temperature increasing,the flux of S-1 membrane,increased from 0.2 kg·m-2·h-1 at 30 ℃ to ca. 1.0 kg·m-2·h-1 at 80 ℃, while the separation factor decreased from 110 to 89.These results showed that silica supports may be more suitable for preparing high performance Silicalite-1 membranes.展开更多
A silicalite 1 zeolite membrane was in situ crystallized from a layer of silica species prepared by a novel method of low temperature chemical vapor deposition (LTCVD) on a porous cordierite substrate. XRD patterns sh...A silicalite 1 zeolite membrane was in situ crystallized from a layer of silica species prepared by a novel method of low temperature chemical vapor deposition (LTCVD) on a porous cordierite substrate. XRD patterns show that the membrane consists of MFI type zeolite crystals. The investigation with SEM indicats that the membrane is about 50 μm thick, and covered with well intergrowth MFI zeolite crystals of about 10 μm in size. The EDX analysis confirms that the membrane is composed of silica in the absence of Al, indicating high silica MFI(Silicalite 1) zeolite grown on the support. The ratio of pure gas permeation is 296 for H 2/ iso butane and 13.7 for n / iso butane at room temperature respectively, confirming that the membrane synthesized on the support of cordierite is high quality without pinhole.展开更多
文摘The growth and orientation of zeolite crystals on a glass substrate was investigated by changing the roughness and setting of the substrate surface.The orientation control of crystals on the glass substrate was achieved.It was found that the setting and treatment of the glass substrate had a substantial effect on crystal orientation.When the substrate surface was upward, the preferential growth of crystal was along the a-axis.However, the preferential growth of crystal was along b-axis when the substrate surface was downward.According to experimental results, a film formation mechanism was proposed to account for the growth and orientation of crystals on the glass substrate.
文摘Synthesis of high performance Silicalite-1 zeolite membranes on silica tubes was first reported in this paper.After two-step in-situ hydrothermal synthesis,well intergrown Silicalite-1 zeolite membranes were synthesized on silica tubes after aging at 75 ℃ for 12 h.The Silicalite-1 zeolite membranes were characterized by SEM.The separation performance towards ethanol/water mixtures was evaluated by pervaporation.With temperature increasing,the flux of S-1 membrane,increased from 0.2 kg·m-2·h-1 at 30 ℃ to ca. 1.0 kg·m-2·h-1 at 80 ℃, while the separation factor decreased from 110 to 89.These results showed that silica supports may be more suitable for preparing high performance Silicalite-1 membranes.
文摘A silicalite 1 zeolite membrane was in situ crystallized from a layer of silica species prepared by a novel method of low temperature chemical vapor deposition (LTCVD) on a porous cordierite substrate. XRD patterns show that the membrane consists of MFI type zeolite crystals. The investigation with SEM indicats that the membrane is about 50 μm thick, and covered with well intergrowth MFI zeolite crystals of about 10 μm in size. The EDX analysis confirms that the membrane is composed of silica in the absence of Al, indicating high silica MFI(Silicalite 1) zeolite grown on the support. The ratio of pure gas permeation is 296 for H 2/ iso butane and 13.7 for n / iso butane at room temperature respectively, confirming that the membrane synthesized on the support of cordierite is high quality without pinhole.
